Combined telephone receiver and phonograph reproducer



Sept 15, 1925. 1,554,012

c LEHRFELD' COMBINED TELEPHONE RECEIVER AND PHONOGRAFH REPRODUCER Filed June 20; 1924 2 Shets-Sheet 1 X Y INVENZOR. a'wia flwzw 0612i BY J I ATTORNEYS.

1,554,012 g. LEHRFELD VER AND PHONOGRAPH REPRODUCER Sept. 15,1925.

COMBINED TELEPHONE RECEI File June 20, 1924 2 Sheets-Sheet 2 IN VEN TOR.

A TTORNEYS.

Patented Sept. 15, 1925.

ITED STATEd CHARLES LEI-IRFEID, 9F NEWARK, NEW JERSEY.

COMBINED TELEPHONE RECEIVER AND PHO'NOGRAPH REPRODUCEB.

Application filed June 20, 1924 Serial No. 721,154.

'J'o all whom it may concern: v

Be itknown that 1, CHARLES LnHRrnLo, a citizen of the United States, residing at Newark, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Combined Telephone Receivers and Phonograph Reproducers; and I dohereby declare the following to be a full, clear, and exact description in of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had "tattle accompanying drawings, and to charactors ofi-eference marked thereon, which form a part of this specification.

This invention relates, generally, to a novel combined telephone receiver and phonograph reproducer adapted to provide a convenient device whereby a phonograph reproducer with its amplifying horn element may also be utilized as a loud speaker in connection with wireless telephone receiving sets, all in such manner that the device may function as a-sound reproduccr common to both a phonograph instrument and a radioreceiving set, and may be selec tively used at will to function in connection with the phonograph elements or with the radio elements without change or necessity for manipulation or alteration in either case. The invention has for its principal object to provide a simple and convenient sound reproducer to serve in common with both a phonograph instrument and a radio receiving set; and the invention has for a further object to provide in a single instrument or device, having a single sound reproducing diaphragm, an clcctro-magnctic means for vibrating said, sound. reproducing diaphragm and a mechanical means for also vibrating said sound reproducing diaphragm. j

The invention has for a further object to provide a novel means for adjusting the 3' electromagnetic means relative to the sound reproducing diaphragm without ii'iterfering with or in any way disturbing the fixed connection and relation of the mechanical dia- 'ihragm vibrating means relative to said diaphragm.

Other objects of this invention, not at this time more part cularly enumerated, will be clearly unders od from the following detailed description of the same.

With the various objects of this invention in view, the same consists, primarily, in the novel combined telephone receiver and phonograph reproducer hereinafter set forth; and, the invention consists, furthermore, in the novel arrangements and combinations of the various devices and parts, as wellas in the details of the construction -embodying the principles of this invention;

Figure 2 is a rear face view of the same; Figure 3 is a front face view of the same with the cover plate and diaphragm removed; Figure at is a side elevation of the same; Figure 5 is a transverse section, taken on line .35 in Figure 1; Figure 6 is another transverse section, taken on line 66 in Figure l; and Figure 7 is a rear face view of the cover plate and diaphragm, showing also the mechanical means for vibrating the latter, when. used as a phonograph reproducer..

Similar characters of reference are employed in all of the hereinabove described views. to indicate corresponding parts.

Referring now to said drawings, thereference character 8 indicates the main casing of the novel combined telephone reccivcr and phonograph reproduccr, the same having an open forward side and a backwall 9 to close its rear side. The open side of said casing 8 is provided with anoutwardly projected annular marginal flange 10. The reference character 11 indicates a cover-plate provided with a central opening 12 surrounded at its outer end with a for wardl-y projecting throat flange 13, whereby a union with a tone-arm and amplifying born (not shown) may be effected. Said cover plate 1.1 is provided in its rear face with a counter-sunk seat 14: for the reception of a suitable sound reproducing diaphragm I15. Said sound reproducing diaphragm may be made of mica or any other suitable material. In assembling the diaphragm with the casing and cover plate, so that the same extends across the. open side of the casing, I prefer to employ a suitable keeper ill) throng which serves as a stop will over ap and couple with ring or washer 16, which overlaps the marginal edge portions of the diaphragm, to thus retain and bind the latter in the seat 14 of the cover plate, the outer portions of said keeper ring or washer 16 being clamped intermediate the outer marginal portions of the cover plate and the marginal flange of the casing, when .the cover plate is secured. to said flange ltl/by the fastening screws 17.

Theelectrdmagnetic means for vibrating the sound reproducing diaphragm comprises the following mechanism. Disposed within the interior chamber 1.8 provided by the casing 8 is a carrier plate 19 preferably made of a rigid insulating material such, e. g. as bakelite. "Molded lnto'said carrier plate 19, or otherwise suitably aflixed time to, so as to project rearwardly therefrom, is a threaded. shank 20. Said threaded shank 20 pro'ects exteriorly frtn said casing 8 a central opening 21 provided in the back wall 9. A sprin element 20 is interposed between the bee -Wall 9 of said casing 8 and the rear face of said carrier plate 19, the tension of which normally presses said carrier plate forwardly toward the diaphragm ,15; Threaded upon the exteriorly pro ecting end ofsaid shank 20 is an adjusting nut 22, which is provided at its inner end with a chambered portion Secured upon said shank 20, within said chambered portion 23 of the nut 22, are lock-nuts 24, which, when properly peeltioned and locked on said shank, serve as a stop for limiting the outward. or rearward movement of the shank and carrier plate, when the shank is actuated in outward di rection by the adjusting nut 22. The free end of the shank 20 is rovided with an enlarged head 25, suita ly secured thereto,

for limiting the inward or forward movement of the shank and carrier plate, when the shank is 'actw in inward direction by the adjusting nut 22. Su ported upon the outer or torward face 0 said carrier plate 19 are a pair of magnetic core pieces 26 and 27 of opposite polarity, which are aligned diametrically upon the carrier plate, and which respectively possess at their free ends right angled outward extensions 26 and 27', upon which are respectively mounted electro-magnetic coil windings 28 and 29. Permanent magnets 30 and 31 are also associated'with said core pieces 26 and 27, the same being each of semi-circular form, andso disposed relatively to the core pieces, that the respective positive oles of said permanent magnets the one core piece 26 to produce a positive polarity as to said core piece 26, while the respective negative poles of said permanent magnets will overlap and couple with the other core piece 27 to produce a negative polarity as to said is supported upon the core pidce 27. Said core-pieces 26 and 27' and the permanent magnets 30 and 31 are,

both secured to said carrier'plate 19 and retained in the above described operative assembled relation, by means of fastening screws 32 which extend upwardly through the carrier plate and respective core-pieces,

to screw into keeper clips 33 which bridge the adjacent opposed ends of the permanent magnets 30 and 31, so as to both retain the same in place and also bind the same respectively in connection with the respective corepieces. In order not to interfere with or disturb the polarity of the permanent magnets, said keeper clips are made of any su1table rigid non-magnetic material, such, for

example, as brass or other non-magnetic inctal. The electr c-magnetic coil windings 28 and 29 are connectedin series, and suitable bindin posts 34; and 35 are provided to receive t e attachment of their free terminal wires, and at the same time serve to connect the conductors 36 from and to a rad shown),

and 37 leading io receiving set (not whereby the electro-magnetic means for .vibrating the diaphragm 15 may be acis' provided with a suitably cured centrally to the inner or rear face of said diaphragm 15, in any suitable manner, as, e. g.-by'cementing or otherwise, isan armature piece 40, preferably consisting of -5 disc of soft iron, which is opposed to the ends of the core-pieces 26 and 27 and subject to the attraction and repulsion thereof.

Since the above described electro-magnetic means for vibrating the diaphragm 15 carrier-plate 19, and since the carrier plate is arranged for move ment toward or away from the diaphragm, it is possible to delicately adjust the electromagnetic means relative to the diaphragm so that the most efiective cooperation be tween the same may be easily maintained. If, e. g., it is desired to adjustthe electromagnetic means toward the diaphragm, the adjusting nut 22 is backed. upon the shank 20, with the result that the spring element 20 will thrust the carrier glaten forward; if, however, it is desired to withdraw the clectro-magnetic means away from the dlfl, phragm, the adjusting nut 22 is turned in wardly upon the shank 20, thus forcibly drawing back the carrier plate against the tension of the spring element 20' The means for mechanically vibrating the diaphragm 15, through the agency of a phonograph record, comprises a suitable fulpassing between the electro-magnetic coil windings 28 and 29. The inner extremity of said arm is provided with a forwardly turned substantially right angled extension 'or terminal member 47 which engages and is permanently secured to the rear side of the diaphragm 15 by attachment to the center of the armature piece 40. The outer end of said stylus lever 44 is formed to provide a stylus or needle receiving socket piece 48,

in which the usual phonograph stylus or needle 49 is operatively mounted and secured by a set screw 50 in the usual manner. It will be apparent that when the stylus or needle 49 is engaged by a rotated phonograph record, the stylus lever 4.4 will be oscillated on its fulcrum to thereby pro duce mechanically induced sound reproducingvibrations of the diaphragm 15.

From the above description it will be quite evident that my above-described invention provides a very compact simple and convenient sound reproducing device, by means of which the sound reproduction may be produced mcchai ,cally through the agency of the usual phc graph mechanism, or electrically through in agency of electrical impulses transmitted by a radio receiving set, so that a common sound reproducing diaphragm may be selectively actuated by either method at will, without necessitatiug any"change-over manipulations or alterations of either position or arrangement of the sound reproducing device of'any-of its parts.

Havingthus descr1bed my invention, I

l. in a sound'reproducing device, a 'casng open at its forward side, a diaphragm secured across the open side of said casing, an oscillatable stylus lever, means to fulcrum said stylus lever, the inner arm of said stylus lever being secured centrally to said 2. In a sound reproducing device, a casing open at its tor-ward side, a diaphragm secured across the open side of said casing, an oscrllatable stylus lever, means to fullcrum said stylus lever,'tl1e inner arm of said stylus lever being'secured centrally to said diaphragm, electro-magnetic devices supported within said casing behind said dia phragm and respectively on opposite sides of said stylus lever, said diaphragm having an armature piece connected with its rear face in opposition to said electro-magnetic devices, all whereby said diaphragm may be selectively actuated by either said stylus lever or. said electro-magnetic devices, and means for adjusting said electrdmagnetic devices-toward or away from said diaphra'gm.

3. In a sound reproducing device, a casing open at its forward side, a diaphragm secured across the open side of said casing, an oscillatable stylus lever, means to ful cruni said stylus lever, the inner arm of said stylus lever being secured centrally to said diaphragm, electro-magnetic devices of op posits polarity supported within said casing behind said diaphragm and respectively on opposite sides of said stylus lever, saiddiaphragm having an armature piece connected with its rear face in opposition to said electro-magnetic devices, all whereby said diaphragm may be selectively actuated by either said stylus lever or said electro-ma netic devices, and means for adjusting said electro-magnetic devices toward or away from said diaphragm, comprising a movable supporting plate upon which said electro-magnetic devicesare secured, said su porting plate having a rearwardly extend ing threaded shank projecting exteriorly through, the rear wall of said casing, spring means for normallythrusting said supporting plate forward toward said diaphragm, and an adjusting nut threaded upon the exterior end of said shank to produce longitudinal movement of the latter in either direction. a, V Y

4. In a sound reproducing device, a casing open at its Eorward side,j'a diaphragm secured across the open side of said casing, an oscillatable stylus lever, means tov fulcr'um said stylus lever, the inner arm of said stylus lever being secured centrally to said diaphragm, electro-magnctic devices Tof opposite polarity supported within said casing behind said diaphragm and respectively on opposite sides of said stylus lever, said diaphragm having an armature piece connected with its rear face in opposition to said clectrounagnctic devices, all whereby said diaphragm may be selectively actuated by either said stylus lever orisaid electro magnetic devices, and means for adjusting said electromagnetic devices toward or awa' from said dia Jhra m com risi'n a a: a y c:

movahie supporting pints: upon which said electm-magnetic (hwicus are sct'urmi, said supporting plane having a reurwardly extending threaded shank projecting extariurly through the rear Willi 0f Saicl raising,

'spring means for normally thrusting: said supporting piate forward toward said diaphragm, an adjusting: nut threaded upon the exterior end of said shank to produce inn-gifnriinai movement of the latter in 10 either direction, and stop devicps for limiting thra mdvement f said shank in either dimctitlih in ir =mmmy,1tha: I (:iaim the invewlion P'L forth above I have hereunto set my hand 5 

